WDPN31 PGTW 120300 MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/PROGNOSTIC REASONING FOR TROPICAL STORM 29W (PAKHAR) WARNING NR 006// RMKS/ 1. FOR METEOROLOGISTS. 2. 6 HOUR SUMMARY AND ANALYSIS. SUMMARY: INITIAL POSITION: 20.1N 129.6E INITIAL INTENSITY: 50 KTS GEOGRAPHIC REFERENCE: 397 NM SOUTH-SOUTHEAST OF KADENA AB MOVEMENT PAST 6 HOURS: NORTHEASTWARD AT 15 KTS SIGNIFICANT WAVE HEIGHT: 17 FEET SATELLITE ANALYSIS, INITIAL POSITION AND INTENSITY DISCUSSION: ANIMATED MULTISPECTRAL SATELLITE IMAGERY (MSI) DEPICTS PERSISTENT DEEP CONVECTION WITH A STRONG CORE WRAPPING AROUND A LOW-LEVEL CIRCULATION CENTER (LLCC), WHICH IS COMPLETELY OBSCURED BY A CENTRAL DENSE COVER. TROPICAL STORM PAKHAR IS STILL INTENSIFYING WITH COLD CLOUD TOP TEMPERATURES REMAINING AROUND THE -70C RANGE, WITH YET ANOTHER BURST OF OVERSHOOTING TOPS REACHING -89C. A WELL-TIMED BULLSEYE FROM A 120037Z METOP-B ASCAT IMAGE LENDS HIGH CONFIDENCE IN THE INITIAL PLACEMENT. THE INITIAL INTENSITY IS ASSESSED WITH HIGH CONFIDENCE AND REMAINS HEDGED SLIGHTLY HIGHER THAN MULTIPLE AGENCIES FIXES LISTED BELOW AND THE ASCAT IMAGE. TS PAKHAR AT THE CURRENT ANALYSIS IS A HIGHLY SYMMETRICAL SYSTEM AND IS ONLY SLIGHTLY IMPACTED BY THE UNFAVORABLE REGION OF STRONG (25-30KTS) VERTICAL WIND SHEAR (VWS) TO THE NORTH. STRONG POLEWARD OUTFLOW IS NOW THE MAIN VENTILATION FOR TS 29W, AND THE SEA SURFACE TEMPERATURES REMAIN WARM (28C-29C). INITIAL WIND RADII BASIS: SCATTEROMETER DATA FROM A 120037 METOP-B IMAGE. CURRENT STEERING MECHANISM: NORTHWEST PERIPHERY OF A DEEP-LAYER SUBTROPICAL RIDGE (STR) CENTERED WELL TO THE EAST-NORTHEAST. AGENCY DVORAK AND AUTOMATED FIXES: PGTW: T3.0 - 45 KTS RJTD: T2.5 - 35 KTS KNES: T3.5 - 55 KTS CIMSS ADT: 57 KTS AT 112340Z FORECASTER ASSESSMENT OF CURRENT ENVIRONMENT: MARGINALLY FAVORABLE VWS: 30+ KTS SST: 28-29 CELSIUS OUTFLOW: STRONG POLEWARD ANALYSIS CONFIDENCE: INITIAL POSITION: HIGH INITIAL INTENSITY: HIGH INITIAL WIND RADII: HIGH 3. FORECAST REASONING. SIGNIFICANT FORECAST CHANGES: THERE ARE NO SIGNIFICANT CHANGES TO THE FORECAST FROM THE PREVIOUS WARNING. FORECAST DISCUSSION: TS 29W WILL TRACK TO THE NORTHEAST AS IT REMAINS UNDER THE STEERING INFLUENCE OF THE STR TO THE EAST-NORTHEAST OVER THE NEXT 12 HOURS. THEREAFTER, THE UPPER-LEVEL CIRCULATION WILL BEGIN TO DECOUPLE FROM THE LOWER CIRCULATION DUE TO THE STRONG VWS, WHICH WILL CONTINUE TO COMBAT THE LLCC. AT OR NEAR TAU 24, TS PAKHAR LLCC IS EXPECTED TO TURN TOWARD THE SOUTHEAST AND THEN SOUTH-SOUTHWEST THROUGH THE REMAINING FORECAST PERIOD ONCE IT FULLY DECOUPLES THE UPPER-LEVEL FROM THE LOWER-LEVEL CIRCULATION. BY TAU 36, THE LLCC WILL ALSO BEGIN ENCOUNTERING AN INFLUX OF STRONGER LOW AND MID-LEVEL DRY AIR, WHICH WILL ENGULF THE MOISTURE AS THE SYSTEM COMPLETELY DISSIPATES OVER THE EASTERN PHILIPPINE SEA BY TAU 48 IF NOT SOONER. MODEL DISCUSSION: MOST OF THE NUMERICAL MODEL GUIDANCE REMAINS CONVINCED ON THE OVERALL TRACK MAKING THE SOUTHEAST TURN WITHIN THE NEXT 12 TO 24 HOURS. THE EXACT TIMING AND SHARPNESS OF THE TURN CONTINUE TO VARY GREATLY FROM RUN TO RUN BETWEEN EACH OF THE MODEL SOLUTIONS. THE SHARPEST TURNING MODELS ARE FROM THE GFS AND ITS ENSEMBLE SOLUTION, WHICH MAKE A COMPLETE U-TURN SOUTHWEST SHORTLY AFTER TAU 12. THE REMAINING MODELS DO NOT FORECAST THE SYSTEM TURNING NEAR AS SHARP AND TURN IT SOUTHEAST JUST AFTER TAU 24. THE INCONSISTENCIES BETWEEN EACH OF THE MODEL RUNS LEND ONLY LOW CONFIDENCE IN THE OVERALL JTWC TRACK. INTENSITY GUIDANCE REMAINS MIXED, WITH THE PEAK INTENSITY REMAINING AT 50 KNOTS, DECREASING FROM TAU 12 UNTIL THE END OF THE FORECAST PERIOD BY TAU 48, LENDING ONLY MEDIUM CONFIDENCE IN THE JTWC INTENSITY FORECAST. FORECAST CONFIDENCE: TRACK 0 - 72 HR: LOW INTENSITY 0 - 72 HR: MEDIUM// NNNN